Long-term entrapment and temperature-controlled-release of SF₆ gas in metal–organic frameworks (MOFs)

• Hana Bunzen,
• Andreas Kalytta-Mewes,
• Leo van Wüllen and
• Dirk Volkmer

Beilstein J. Nanotechnol. 2019, 10, 1851–1859, doi:10.3762/bjnano.10.180

• cluster DFT calculations, as described previously [44]. ESP values for the symmetry unique atoms of MFU-4 and SF6 are displayed in the Supporting Information File 1 in Figure S13. Prior to the potential energy scan, all atomic positions of the MFU-4 unit cell were fully relaxed at tight convergence

The impact of crystal size and temperature on the adsorption-induced flexibility of the Zr-based metal–organic framework DUT-98

• Simon Krause,
• Volodymyr Bon,
• Hongchu Du,
• Rafal E. Dunin-Borkowski,
• Ulrich Stoeck,
• Irena Senkovska and
• Stefan Kaskel

Beilstein J. Nanotechnol. 2019, 10, 1737–1744, doi:10.3762/bjnano.10.169

• flexible MOFs are being reported and their use in the areas of storage [4], separation [5] and sensing [6] of gases is being evaluated; their structural flexibility and adsorption behavior can be manipulated by applying chemical functionalization to the ligand [7] and metal cluster [8]. However, recent

• cluster of 1.5 nm, which is in good agreement with the lattice parameter and the inter-cluster distance of the DUT-98op crystal structure (Supporting Information File 1, Figure S8). The regular arrangement of the clusters indicates a high symmetry that matches the tetragonal symmetry in DUT-98op. In

• contrast, the DUT-98cp phase would exhibit a different microscopic structure due to the lower, monoclinic symmetry. In addition, no missing cluster or linker defects could be detected that are well-known for Zr-MOFs [36][37], demonstrating that the observed behavior does not depend on increasing

Direct observation of oxygen-vacancy formation and structural changes in Bi₂WO₆ nanoflakes induced by electron irradiation

• Hong-long Shi,
• Bin Zou,
• Zi-an Li,
• Min-ting Luo and
• Wen-zhong Wang

Beilstein J. Nanotechnol. 2019, 10, 1434–1442, doi:10.3762/bjnano.10.141

• clusters on the nanoflake surfaces, and the oxygen atoms are released from the nanoflakes, while the W–O networks reconstruct to form WO3. A possible mechanism that accounts for the observed processes of Bi cluster formation and oxygen release under energetic electron irradiation is also discussed

• . Local electric fields contribute to the observed process of Bi cluster formation and oxygen release. Our experimental results suggest that the use of energetic electrons in a TEM is an effective means to induce oxygen vacancies or other defects in bismuth tungsten oxides. We suggest that it is possible

Fe₃O₄ nanoparticles as a saturable absorber for giant chirped pulse generation

• Ji-Shu Liu,
• Xiao-Hui Li,
• Abdul Qyyum,
• Yi-Xuan Guo,
• Tong Chai,
• Hua Xu and
• Jie Jiang

Beilstein J. Nanotechnol. 2019, 10, 1065–1072, doi:10.3762/bjnano.10.107

• ) Nonlinear transmission measurement setup for the Fe3O4 SA. (d) Nonlinear optical absorption characteristics of the FONP-based SA. (a) Energy-dispersive spectroscopy, (b) Raman spectroscopy, (c) X-ray diffraction pattern, and (d) UV–vis–NIR spectrum of the as-prepared Fe3O4 cluster-structured nanoparticles

Correlation of surface-enhanced Raman scattering (SERS) with the surface density of gold nanoparticles: evaluation of the critical number of SERS tags for a detectable signal

• Vincenzo Amendola

Beilstein J. Nanotechnol. 2019, 10, 1016–1023, doi:10.3762/bjnano.10.102

• interdipole spacing much smaller than the wavelength of interest [44][45][47]. Therefore, in the present case, 4 × 105 dipoles were used for the target, corresponding to an interdipole spacing of less than 0.5 nm. Results and Discussion In this study, AuNTs consist of a cluster of Au nanoparticles aggregated

Structural and optical properties of penicillamine-protected gold nanocluster fractions separated by sequential size-selective fractionation

• Xiupei Yang,
• Zhengli Yang,
• Fenglin Tang,
• Jing Xu,
• Maoxue Zhang and
• Martin M. F. Choi

Beilstein J. Nanotechnol. 2019, 10, 955–966, doi:10.3762/bjnano.10.96

• precipitation technique can reduce the ability of a solvent to disperse clusters by adding a miscible non-solvent to the cluster agglomeration point. The larger clusters are first aggregated due to the greater van der Waals attraction between the clusters, and the clusters aggregated can be precipitated by

• %, F72%, and F90%). Due to the fractionation process, these AuNCs are monodisperse relative to the crude product. The AuNC image was analyzed and a histogram was prepared for all AuNCs fractions, as shown in the right panel of Figure 3. The average cluster size is 3.0 ± 0.6, 2.3 ± 0.5, 1.7 ± 0.4 and 1.2

• clusters at the median cluster size, especially for small AuNCs. For example, 6% of the crude product of AuNCs was 1.2 nm in diameter but after the fractionation process, 26% of the AuNCs in the fraction of F72% were 1.2 nm. This indicates that the composition of the water/acetone mixed solvent greatly

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• asking for complex models in order to be fully understood. In [26], the substrate has been treated as an additional ligand. By attaching this cluster to the metal center, a model for the formation of molecule–surface bonds was proposed. Yet, the band character of the metallic substrate is partially lost

Self-assembly and wetting properties of gold nanorod–CTAB molecules on HOPG

• Imtiaz Ahmad,
• Floor Derkink,
• Tim Boulogne,
• Pantelis Bampoulis,
• Harold J. W. Zandvliet,
• Hidayat Ullah Khan,
• Rahim Jan and
• E. Stefan Kooij

Beilstein J. Nanotechnol. 2019, 10, 696–705, doi:10.3762/bjnano.10.69

• nonwetting substrates, suspension droplets typically leave a deposit of particles after evaporation of the solvent in the form of a cluster [54][55][56]. For instance, to maintain its contact angle on nonwetting surface like HOPG, the inward motion of the shrinking droplet will sweep away all particles from

• the HOPG terraces except those that settle on the wall of the step edges. Consequently, a cluster of deposited particles will be observed in the end whereas other areas of the substrate will be free from such particles. Thus, in principle, no particles should be found on the nonwetting HOPG terraces

Quantification and coupling of the electromagnetic and chemical contributions in surface-enhanced Raman scattering

• Yarong Su,
• Yuanzhen Shi,
• Ping Wang,
• Jinglei Du,
• Markus B. Raschke and
• Lin Pang

Beilstein J. Nanotechnol. 2019, 10, 549–556, doi:10.3762/bjnano.10.56

• experimental value of ≈14, which further agrees with a value of 12 obtained from an earlier theory of small cluster models of a metal–benzenethiol complex excited at 785 nm wavelength [16]. Our values further agree well with experimental CE values of ≈11 for 785 nm and 8 ± 2 for 633 nm obtained on a rough gold

• spectral variations are found to be sensitive to the electronic structures of the metal–molecule hybrid state. The calculated electronic excitation spectra of different complexes are quite dissimilar, which is related to the relative orientation of the benzene ring with respect to the cluster, the local

• molecule–metal complex, which includes the relative orientation of the molecule with respect to the metal cluster, the local symmetry of molecule, and the proximity of the particular vibrational mode to the binding site all contribute to SERS. Besides, specific properties of the Raman response are strongly

Gold nanoparticles embedded in a polymer as a 3D-printable dichroic nanocomposite material

• Lars Kool,
• Anton Bunschoten,
• Aldrik H. Velders and
• Vittorio Saggiomo

Beilstein J. Nanotechnol. 2019, 10, 442–447, doi:10.3762/bjnano.10.43

• dependent study shows the formation of small gold nuclei that in time cluster together forming nanowire-like structures concomitant to the first color change. The second change of color, from ink-black to purple, is accompanied by an enhancement of the scattering, giving the purple solution a brown

Nitrous oxide as an effective AFM tip functionalization: a comparative study

• Taras Chutora,
• Bruno de la Torre,
• Pingo Mutombo,
• Jack Hellerstedt,
• Jaromír Kopeček,
• Pavel Jelínek and
• Martin Švec

Beilstein J. Nanotechnol. 2019, 10, 315–321, doi:10.3762/bjnano.10.30

• (111) system, revealing the formation of small 2D clusters, preferentially located at the kinks of the characteristic herringbone structure. Their variable size is typically a few nanometers in diameter. The estimated average apparent height of the cluster formations was 70 pm. After the N2O cluster

• ), which revealed elongated structures; we attribute these to individual flat-lying N2O molecules. In a cluster, typically composed of 5–25 molecules, the N2O molecules have a preferential short-range arrangement of rotationally symmetrical trimers, with intermolecular distances of about 4.3 Å. A DFT

• , due to their slightly different polarization. The calculations reveal that the preferred orientation of the N2O molecules in the clusters is with the O atoms outward (Figure 1b), being 17 meV more stable than the opposite arrangement. Using the optimized geometry of the cluster obtained from DFT

Heating ability of magnetic nanoparticles with cubic and combined anisotropy

• Nikolai A. Usov,
• Mikhail S. Nesmeyanov,
• Elizaveta M. Gubanova and
• Natalia B. Epshtein

Beilstein J. Nanotechnol. 2019, 10, 305–314, doi:10.3762/bjnano.10.29

• greatly hindered. It is also important that the average distance between the centers of closest nanoparticles in the cluster is small, of the order of the particle diameter. Therefore, the strong magneto–dipole interaction within the clusters considerably affects the heating efficiency of the assembly [18

• –dipole interaction within the cluster. A similar effect is also confirmed for clusters of nanoparticles with cubic or combined anisotropy. For example, “protein coronas” around the nanoparticles can keep them separated in a natural way. This effect can be used to improve the ability of magnetite

• ][31] governs the dynamics of the unit magnetization vector of the ith single-domain nanoparticle of the cluster where γ is the gyromagnetic ratio, κ is phenomenological damping parameter, γ1 = γ/(1+κ2), is the effective magnetic field and is the thermal field. The effective magnetic field acting on

Thermal control of the defunctionalization of supported Au₂₅(glutathione)₁₈ catalysts for benzyl alcohol oxidation

• Zahraa Shahin,
• Hyewon Ji,
• Rodica Chiriac,
• Nadine Essayem,
• Franck Rataboul and
• Aude Demessence

Beilstein J. Nanotechnol. 2019, 10, 228–237, doi:10.3762/bjnano.10.21

• ][14][15]. The Au25(SR)18 gold thiolate cluster, the captain of the gold nanoclusters ship, is a thermodynamically stable cluster consisting of 25 gold atoms and protected by 18 thiolate ligands [16]. This gold thiolate cluster has been widely studied for its high potential in different domains of

• , its activity decreased [19]. In contrast, fully defunctionalized clusters are essential for CO [20], alcohol [17][21], cyclohexane [22] and styrene [23][24] oxidation, as well as nitrobenzene hydrogenation [24]. Recently, a partially calcined Au38(2-phenylethanethiolate)24 cluster supported on

• °C for 4 hours. The final product Au25(SG)18 was filtered, isolated by precipitation with methanol and centrifuged (10000 rpm for 15 minutes), washed several times with methanol (5000 rpm, 15 minutes), and was air-dried. Synthesis of the composite material Au25(SG)18@ZrO2 Gold cluster deposition Au25

Mechanism of silica–lysozyme composite formation unravelled by in situ fast SAXS

• Tomasz M. Stawski,
• Daniela B. van den Heuvel,
• Rogier Besselink,
• Dominique J. Tobler and
• Liane G. Benning

Beilstein J. Nanotechnol. 2019, 10, 182–197, doi:10.3762/bjnano.10.17

• associated with the diffusion-limited particle–cluster aggregation (DLPCA) mechanism [47][48][49][50][51][52]. The DLPCA growth mode is also evidenced not only by the plateau value of D, but also through the fact that the value of D increases with the size/extent of the aggregates [47][49] expressed

• . This model allowed us to unravel that the formation follows a diffusion limited particle–cluster aggregation (DLPCA) mechanism, which results in relatively densely packed mass-fractal-like aggregates within which non-fractal correlated domains of particles evolve. Furthermore, we used the scattering

Nanoporous water oxidation electrodes with a low loading of laser-deposited Ru/C exhibit enhanced corrosion stability

• Sandra Haschke,
• Dmitrii Pankin,
• Vladimir Mikhailovskii,
• Maïssa K. S. Barr,
• Adriana Both-Engel,
• Alina Manshina and
• Julien Bachmann

Beilstein J. Nanotechnol. 2019, 10, 157–167, doi:10.3762/bjnano.10.15

• supported by the German Research Foundation (DFG) via the bridge funding of the excellence cluster “Engineering of Advanced Materials” (EXC315) and by the German Academic Exchange Service (DAAD) via the German-Russian Interdisciplinary Research Center (projects; C-2016b-2, C-21017a-2). The Raman

Sputtering of silicon nanopowders by an argon cluster ion beam

• Xiaomei Zeng,
• Vasiliy Pelenovich,
• Zhenguo Wang,
• Wenbin Zuo,
• Sergey Belykh,
• Alexander Tolstogouzov,
• Dejun Fu and
• Xiangheng Xiao

Beilstein J. Nanotechnol. 2019, 10, 135–143, doi:10.3762/bjnano.10.13

• (CeFITec), Dept. de Física da Faculdade de Ciências e Tecnologia (FCT), Universidade Nova de Lisboa, Caparica, 2829-516, Portugal 10.3762/bjnano.10.13 Abstract In this work an Ar+ cluster ion beam with energy in the range of 10–70 keV and dose of 7.2 × 1014–2.3 × 1016 cluster/cm2 was used to irradiate

• pressed Si nanopowder targets consisting of particles with a mean diameter of 60 nm. The influence of the target density and the cluster ion beam parameters (energy and dose) on the sputtering depth and sputtering yield was studied. The sputtering yield was found to decrease with increasing dose and

• near 17 keV. The dose and energy dependence of the sputtering yield was explained by the competition of the finite size effect and the effect of debris formation. Keywords: finite size effect; gas cluster ion beam; silicon nanoparticles; smoothing effect; sputtering; Introduction Etching using gas

Time-resolved universal temperature measurements using NaYF₄:Er³⁺,Yb³⁺ upconverting nanoparticles in an electrospray jet

• Kristina Shrestha,
• Arwa A. Alaulamie,
• Ali Rafiei Miandashti and
• Hugh H. Richardson

Beilstein J. Nanotechnol. 2018, 9, 2916–2924, doi:10.3762/bjnano.9.270

• temperature measurement unless a calibration is made under identical conditions. We observed that the peak shape of the S-band changes with 980 nm laser intensity (Figure 3) and with the 980 nm laser excitation time (see below in Figure 5). Figure 3A shows H- and S-band for a single cluster of ca. 1 μm UCNPs

• calibration are shaded in green and brown, respectively, in (A). The slope of the line calculated is −1182 ± 8 K and the intercept is 3.002 ± 0.021. Measurement of temperature of UCNPs at different laser intensities of 980 nm. (A) Photoluminescence spectra of a single cluster of UCNPs of ca. 1 μm size at

Site-controlled formation of single Si nanocrystals in a buried SiO₂ matrix using ion beam mixing

• Xiaomo Xu,
• Thomas Prüfer,
• Daniel Wolf,
• Hans-Jürgen Engelmann,
• Lothar Bischoff,
• René Hübner,
• Karl-Heinz Heinig,
• Wolfhard Möller,
• Stefan Facsko,
• Johannes von Borany and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2018, 9, 2883–2892, doi:10.3762/bjnano.9.267

• density of NCs and even NCs that are connected to the interface are observed in the simulation (see Figure 2b). In general, by carefully comparing Figure 1 with the simulated Si NC bands, presented in Figure 2, one can see that neither the cluster size nor the density matches perfectly. To obtain a

Optimization of Mo/Cr bilayer back contacts for thin-film solar cells

• Nima Khoshsirat,
• Fawad Ali,
• Vincent Tiing Tiong,
• Mojtaba Amjadipour,
• Hongxia Wang,
• Mahnaz Shafiei and
• Nunzio Motta

Beilstein J. Nanotechnol. 2018, 9, 2700–2707, doi:10.3762/bjnano.9.252

• regions were acquired with 10 eV pass energy and about 0.4 eV spectral resolution to discriminate the substructure of the spectral lines. Ar+ ion cluster etching was employed for XPS depth profiling and the calibration was carried out using a typical Mo on glass sample with sputtering rate of 15.5 nm/s

• . Depth profiling was conducted on a 1 × 1 mm2 area with a Ar+ ion beam energy of 10 keV and large cluster size (n = 2000). Results and Discussion Adhesion The first characterization step was the adhesion test performed on Mo layers after deposition on uncoated and Cr-coated glass substrates. All samples

• any Cr or Na signal in the Mo layer, by etching the film via argon gas cluster ions for 4 min before each XPS acquisition until the signal from the substrate was visible. The result is shown in Figure 7 for a Mo/Cr film deposited at 200 W and 3 mTorr (high-resolution spectra of Mo 3d and Cr 2p are

Au–Si plasmonic platforms: synthesis, structure and FDTD simulations

• Anna Gapska,
• Marcin Łapiński,
• Paweł Syty,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2018, 9, 2599–2608, doi:10.3762/bjnano.9.241

• same spectra measured for the as-prepared film and for bulk Au are added. The binding energy of the Au 4f core-level shifts, depending on cluster size, cluster–substrate interactions, cluster morphology and charge transfer between cluster and substrates [23][24]. Additionally, the peak ratio of the Au

• 4f7/2 and 4f5/2 excitations differs from the statistical ratio of 4:3 and the linewidths (FWHM) are not equal. The size of the clusters can also affect the symmetry of the Au 4f7/2 peak on the side of higher binding energies, and the asymmetry increases with decreasing cluster size. In our

High-temperature magnetism and microstructure of a semiconducting ferromagnetic (GaSb)_1−x(MnSb)_x alloy

• Leonid N. Oveshnikov,
• Elena I. Nekhaeva,
• Alexey V. Kochura,
• Alexander B. Davydov,
• Mikhail A. Shakhov,
• Sergey F. Marenkin,
• Oleg A. Novodvorskii,
• Alexander P. Kuzmenko,
• Alexander L. Vasiliev,
• Boris A. Aronzon and
• Erkki Lahderanta

Beilstein J. Nanotechnol. 2018, 9, 2457–2465, doi:10.3762/bjnano.9.230

• was suggested [9] that the ferromagnetic ordering in this case is induced by the interaction of MnSb magnetic clusters with carriers inside the matrix. It should induce carrier spin-polarization and lead to the formation of a long-range ferromagnetic percolation cluster, which includes both MnSb

Surface energy of nanoparticles – influence of particle size and structure

• Dieter Vollath,
• Franz Dieter Fischer and
• David Holec

Beilstein J. Nanotechnol. 2018, 9, 2265–2276, doi:10.3762/bjnano.9.211

• indication of a structural feature. However, it is remarkable that the first extremum occurs, in both cases, for a cluster consisting of 13 atoms and the second one for a cluster size of 43 atoms. The number 13 is a so-called “magic number” for cluster sizes; however, the number 43 is far off from the second

• magic number for clusters consisting of 55 atoms. More detailed insight is provided by a thorough ab initio study analyzing the Au55 cluster performed by Holec et al. [53] and Vollath et al. [14]. These studies established the fact that the most stable state of this cluster is glassy. The accompanying

• radius is a crucial problem that may be solved using a correction derived by Holec et al. [53]. The enthalpy of sublimation is determined as the binding energy of the outmost atoms of the particle. Figure 18 displays the binding energy for the atoms of the outmost layer of the glassy Au55 cluster. To

Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

• particles can be of importance. This was demonstrated by MD simulations for gold clusters on HOPG, where a significant reduction of static friction was found by simply increasing the cluster thickness. As a result, the nanostructure becomes elastically stiffer, which goes along with a reduced tendency to

Synthesis of hafnium nanoparticles and hafnium nanoparticle films by gas condensation and energetic deposition

• Irini Michelakaki,
• Nikos Boukos,
• Dimitrios A. Dragatogiannis,
• Spyros Stathopoulos,
• Costas A. Charitidis and
• Dimitris Tsoukalas

Beilstein J. Nanotechnol. 2018, 9, 1868–1880, doi:10.3762/bjnano.9.179

• alternative method to tune the porosity of the NTFs. 3D NTF patterning Cluster beam deposition combined with patterning for fabricating 3D objects has been successfully performed by other groups with techniques such as supersonic cluster beam deposition combined with stencil masks [65][66]. In our case we

• target (99.95%). Due to collisions with Ar gas, cooling of the sputtered metal atoms takes place, leading to a supersaturated metal atom vapor. Collisions between the cooled metal atoms lead to nucleation and growth of initial clusters. Collisions between these initial cluster ‘seeds’ followed by

Nanoscale electrochemical response of lithium-ion cathodes: a combined study using C-AFM and SIMS

• Jonathan Op de Beeck,
• Nouha Labyedh,
• Alfonso Sepúlveda,
• Valentina Spampinato,
• Alexis Franquet,
• Thierry Conard,
• Philippe M. Vereecken,
• Wilfried Vandervorst and
• Umberto Celano

Beilstein J. Nanotechnol. 2018, 9, 1623–1628, doi:10.3762/bjnano.9.154

• (detecting the Li concentration at the surface) and C-AFM (local conductivity) in succession in the same area for the case of the RF-sputtered LMO cathode is shown in Figure 2a. The static SIMS analysis is performed using a Bi3 cluster beam (spot size ca. 70 nm) in the area previously studied by C-AFM